Thank you for asking. I can understand the distress you are through. If you have done lab investigations, and these reports are normal, also shown yourself to a physician and according to him there is no physical cause, in that case the symptoms you are showing can be explained by an anxiety disorder. Persistent thinking or worrying, low energy, not able relax down, bodyache, weakness etc can be a presentation of general anxiety disorder. Associated acidity problem, constipation, weight loss are common issues. I am suspecting an anxiety problem in your case.